SU1219938A1 - Method of determining the outer dead point of internal combustion engine piston and arrangement for accomplishment of same - Google Patents

Abstract

The invention relates to methods and means for testing and diagnosing internal combustion engines. In order to improve the accuracy of the determination of the top dead center, the errors caused by fluctuations in the amplitude of the signal are eliminated. The device works in three modes: preparation, zahshs, reading. In Preparation mode, switch 5 is set to Preparation. The engine is scrolled with the help of a starter, the pulses from the generator of 8 clock pulses (GTI) are fed to the magnetic head 4. In this case there is a magnetic recording of pulses on the parts coupled to the crankshaft. In Record mode, switch 5 is in the off position, switches 6 and 7. in the Record position. The engine is running in starter mode. In this case, the differentiating amplifier registers the moments at which the battery voltage is minimum, the starter current is maximum). At the moment: when fuel is supplied to the cylinder at the output of the sensor 14, the engine, for example, the vibrator installed at the nozzle of the cylinder, appears trigger 9 to state 1. At the same time (L

Description

the element I opens and the pulses from the magnetic head 4 arrive at the counter 13. At the time when the battery reaches the minimum voltage 2, the comparator 3 transfers the trigger 9 to the state O. The counter 13 goes into the storage mode. The falling edge front-end pattern 10 on the falling edge of the trigger pulse 9 generates a pulse, over which information is overwritten from the counter 13 to the counter 12. The content of the counter 13 does not change. In read mode, switches 6 and 7 are in the read position. The engine is in operation. The output pulse of the sensor 14 engine cycles converts the trigger 9 in state 1

 The invention relates to methods and means for testing and diagnosing internal combustion engines.

The aim of the invention is to improve the accuracy.

The drawing shows a structural diagram of the device.

The device contains a differentiating amplifier 1, battery 2, comparator 3, magnetic head 4, switch 5 of preparation mode, switches 6 and 7 of write-read mode, clock pulse generator (GTI) 8, trigger 9, circuit 10 of the trailing edge, AND element 11, counters 12 and 13, the sensor 14. cycles.

The device operates in three modes: Prepare, Record, Read. In Preparation mode, switch 5 is set to Preparation. The engine is rotated by means of a starter., The pulses from the GTI 8 are fed to the magnetic head 4. In this case, a magnetic recording of the pulses on the parts coupled to the crankshaft occurs. In the Record mode, the switch 5 is in the off position, the switches 6 and 7 are in the Record position. The engine is running in starter mode. In this case, the differential 1 manual amplifier registr. With this element And 11

Scientific research institute

opens and the pulses from the magnetic head 4 are fed to the counter 12, operating in the subtraction mode. When the contents of counter 12 become equal to zero, a pulse appears at its output, switching trigger 9 into state O. Element 11 closes and the trailing edge closing circuit 10 along the trailing edge of trigger 9 generates a pulse that rewrites information from Counter 13 into counter 12. The same impulse arrives at the output bus of the device, since it corresponds to the top dead center in the cylinder 2c, pffly 1 mud.

The moments at which the battery voltage is at its minimum (the starter current is at its maximum) are triggered. At the time of supplying fuel to the cylinder, for example, a diesel engine, on the sensor code ,. 14 cycles, such as a vibration transducer mounted on the nozzle of the cylinder, a pulse appears that sets the trigger 9 to 1. In this case, the element

Both it opens and the pulses from the magnetic head 4 arrive at the counter 13. At the moment when the voltage of the battery 2 reaches the minimum value k 3, the Fapat 3 switches the trigger 9 to the zero state.

Counter 13 goes into storage mode. Scheme 10 in the fission of the front along the trailing edge of the pulse of the trigger 9 generates a pulse, through which information is overwritten from

counter 13 to counter 12. The contents of counter 13 do not change.

In the read mode, switches 6 and 7 are in the position of the switch. The engine is in operation. The output pulse of the sensor 14 cycles converts the trigger 9 into one state. In this case, the element And 11 opens, and the pulses with magnetic

heads 4 are fed to counter 12 operating in subtraction mode. When the contents of counter 12 become zero, it will appear at its output.

pulse, switching trigger 9 in ni chi vl l 5 nor right

left state. The circuit 11 is closed, and the circuit 10 inserting the trailing edge along the trailing edge of the trigger 9 generates an impulse that rewrites information from counter 13 to counter 12. This same impulse goes to the output bus of the device, since it corresponds to the top dead center in the cylinder, Introduction New elements and connections allow to improve the accuracy of determining the top dead center due to the fact that errors caused by fluctuations of the signal amplitude are eliminated.

1 formula of invention

 1. The method of determining the top dead center (TDC) of the piston of the internal combustion engine, which consists in measuring the voltage at the battery terminals during the starter mode, registering the time at which this voltage is minimal, and forming a magnetic head with the help of a magnetic head. on parts that are rigidly connected to the crankshaft, then, in the engine operating mode, read these marks using a magnetic head, compare the output signal of the magnetic head with a threshold voltage, and at the moment of their equality form a signal TDC, characterized in that, in order to improve the accuracy of the determination in the starter mode, they are recorded on rigidly connected parts: x with the crankshaft, using a variable magnetic flux preparatory marks with a clock frequency exceeding the maximum frequency of rotation of the engine shaft, form a signal from the sensor cycles, then using a magnetic tin for one revolution of the shaft read and record the number of pulses of clock

Editor T. Kugrsheka

Compiled by N.Patrahaltsev

Tehred .I, Veres Proofreader; E. Sirohman

Order 1316/51 Circulation 778 Subscription VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Branch PPP Patent, Uzhgorod, Proektna St., 4

the frequency between the signal from the engine cycle sensor and the point in time when the battery voltage reaches the minimum value, and in the engine operating mode, a similar reading is performed; the clock frequency pulses until the number fixed in the starter mode is equal to that COOT - Corresponds to the mark VM 1.

2. A device for carrying out the method according to Claim 1, comprising a magnetic head, a write-read mode switch, a control unit, an engine cycle sensor, a comparator, a battery and a differentiating amplifier whose input is connected to a battery, and the output to a comparator, characterized in that, in order to improve the determination accuracy, a preparation mode switch, a clock pulse generator, a trigger, an AND element, a falling edge selection circuit and recording and subtracting counters are introduced into it, and the output of the qi sensor engine operation is connected to the trigger setup input, the reset input of which is connected via a read-read switch to the comparator output or to the output of the detracting counter, and the output of the trigger is connected to the reset input of the subtractive counter and the output of the device, and directly to the first input of the element I, the second input of which is connected via normally closed contacts of the preparation mode switch to the magnet head, which in the preparation mode is connected clock generator, wherein the output element and via a switch-mode recording s.chityvany .schetnymi connected to the inputs of the subtractor and the recording of counters The discharge outputs of which are interconnected.

Claims (2)

The claims 1. The method of determining the top dead center (TDC) of the piston of an internal combustion engine, which consists in the fact that during the starting mode, measure the voltage at the terminals of the batteries, record the point in time when this voltage is minimum, and form using the magnetic head marks on the details rigidly connected to the crankshaft, then, in the operating mode of the engine, these marks are read using a magnetic head, the output signal of the magnetic head is compared with the threshold voltage and at the time of their equalities generate a TDC signal, characterized in that, in order to increase the accuracy of determination in the starter mode, preparatory marks with a clock frequency exceeding the maximum engine shaft speed are recorded on parts rigidly connected to the crankshaft, they form a signal from the cycle sensor , then using a magnetic head for one revolution of the crankshaft, the number of pulses of the clock frequency between the signal from the engine cycle sensor and the moment th time when the battery voltage reaches the minimum znache5 Nia and in the working mode of the engine is carried out a similar reading clock pulses to their equality mimenta recorded at starter mode number that soot10 sponds mark BM 1. 2. The device for implementing the method according to claim 1, comprising a magnetic head, a write-read mode switch, a control unit, 15 an engine cycle sensor, a comparator, a battery and a differentiating amplifier, the input of which is connected to the battery, and the output to the comparator, characterized 20 by the fact that, in order to increase the accuracy of determination, a preparation mode switch, a clock pulse generator, a trigger, an And element, a trailing edge 25 allocation circuit and recording and subtracting counters are introduced into it, and the output of the engine cycle sensor is connected to the trigger installation input, the reset input of which through the 3Q switch, the write-read mode reader is connected to the output of the comparator or to the output of the subtracting counter, and the trigger output is connected via the trailing edge allocation circuit to the reset subtraction input counter and the output of the device, and directly to the first input of the AND element, the second input of which is connected through normally closed contacts, of the preparation mode switch with a magnetic head, which in preparation mode is connected to a clock pulse, the output of the And element through the mode switch write-s. readings connected to the counting inputs of the subtracting and recording counters, the bit outputs of which are interconnected.